Late-onset neonatal sepsis: genetic differences by sex and involvement of the NOTCH pathway.

BACKGROUND: Late-Onset Neonatal Sepsis (LOS) is a rare condition, involving widespread infection, immune disruption, organ dysfunction, and often death. Because exposure to pathogens is not completely preventable, identifying susceptibility factors is critical to characterizing the pathophysiology and developing interventions. Prior studies demonstrated both genetics and infant sex influence susceptibility. Our study was designed to identify LOS associated genetic variants. METHODS: We performed an exploratory genome wide association study (GWAS) with 224 LOS cases and 273 controls from six European countries. LOS was defined as sepsis presenting from 3 to 90 days of age; diagnosis was established by clinical criteria consensus guidelines. We tested for association with both autosomal and X-chromosome variants in the total sample and in sex-stratified analyses. RESULTS: In total, 71 SNPs associated with neonatal sepsis at p < 1 × 10-4 in at least one analysis. Most importantly, sex-stratified analyses revealed associations with multiple SNPs (28 in males and 16 in females), but no variants from single-sex analyses associated with sepsis in the other sex. Pathway analyses showed NOTCH signaling is over-represented among genes linked to these SNPS. CONCLUSION: Our results indicate genetic susceptibility to LOS is sexually dimorphic and corroborate that NOTCH signaling plays a role in determining risk. IMPACT: Genes associate with late onset neonatal sepsis. Notch pathway genes are overrepresented in associations with sepsis. Genes associating with sepsis do not overlap between males and females. Sexual dimorphism can lead to sex specific treatment of sepsis.

ATG5 gene expression analysis supports the involvement of autophagy in microangiopathic complications of type 2 diabetes.

BACKGROUND AND AIMS: Type 2 diabetes (T2D) hyperglycaemia alters basal autophagy. Since autophagy is an essential cellular process, our aim was to investigate the ATG5 (autophagy-related 5) gene expression level and genetic variants in a cohort of diabetic patients, characterized for the presence of microangiopathic complications. METHODS AND RESULTS: the expression levels of ATG5 were evaluated in PBMCs from 48 T2D patients with an extensive evaluation for microangiopathic complications. Our analyses revealed a significant lower expression of ATG5 in T2D patients with retinopathy compared to those without retinopathy. We also highlighted a significant lower expression of ATG5 in T2D patients with early-cardiovascular autonomic neuropathy compared to those without it, after correction for sex, age, body mass index and levels of hemoglobin A1c. CONCLUSION: our results highlight that dysregulation in the autophagy process could be involved in the development of severe microangiopathic complications.

Fever in systemic lupus erythematosus: associated clinical features and genetic factors.

OBJECTIVES: Fever has been recently included in the new 2019 EULAR/ACR classification criteria for systemic lupus erythematosus (SLE). Thus, we investigated the possible association of fever with other clinical disease manifestations. Then, we analysed a panel of 30 SNPs to verify their possible contribution to the pathogenesis of this constitutional symptom. METHODS: In this retrospective study we collected clinical/laboratory features in a SLE cohort, including the occurrence of fever (body temperature >37.5°C, excluding infective aetiology). A phenotype-genotype correlation analysis was carried out. RESULTS: We evaluated 167 patients (M/F 12/155, median age at the disease diagnosis 30 years, IQR 17; median disease duration 240 months, IQR 156). Seventy patients (41.9%) reported fever, significantly associated with: serositis and haematological manifestations (p=0.02 and p=0.00001, respectively). A significant association between fever and leukopenia (p=0.003), haemolytic anaemia (p=0.04), and thrombocytopenia (p=0.04) was observed. In addition, significantly higher median SLICC Damage Index (SDI) values were observed in patients with fever in comparison with those without [2 (IQR 3) vs. 1 (IQR 2); p=0.005]. The genotype/phenotype analysis showed an association between fever and the rs13361189 of Immunity Related GTPase M (IRGM) gene (p=0.003; OR 3.89, CI 1.16-13.03), confirmed also in multivariate logistic regression analysis (p=0.028, B=1.39). CONCLUSIONS: The association between IRGM rs13361189 polymorphism and the occurrence of inflammatory fever, could provide new insights into the role of genetic background in the pathogenesis of this SLE-related feature.

mRNA expression analysis confirms CD44 splicing impairment in systemic lupus erythematosus patients.

BACKGROUND: Systemic Lupus Erythematosus (SLE) is a complex chronic autoimmune disease characterized by several immunological alterations. T cells have a peculiar role in SLE pathogenesis, moving from the bloodstream to the peripheral tissues, causing organ damage. This process is possible for their increased adherence and migration capacity mediated by adhesion molecules, such as CD44. Ten different variant isoforms of this molecule have been described, and two of them, CD44v3 and CD44v6 have been found to be increased on SLE T cells compared to healthy controls, being proposed as biomarkers of disease and disease activity. The process of alternative splicing of CD44 transcripts is not fully understood. We investigated the mRNA expression of CD44v3 and CD44v6 and also analyzed possible CD44 splicing regulators (ESRP1 molecule and rs9666607 CD44 polymorphism) in a cohort of SLE patients compared to healthy controls. METHODS: This study involved 18 SLE patients and 18 healthy controls. Total RNA and DNA were extracted by peripheral blood mononuclear cells. The expression study was conducted by quantitative RT-polymerase chain reaction, using SYBR Green protocol. Genotyping of rs9666607 SNP was performed by direct sequencing. RESULTS: CD44v6 mRNA expression was higher in SLE patients compared to healthy controls (p = 0.028). CD44v3/v6 mRNA ratio in healthy controls was strongly unbalanced towards isoform v3 compared to SLE patients (p = 0.002) and decreased progressively from healthy controls to the SLE patients in remission and those with active disease (p = 0.015). The expression levels of CD44v3 and CD44v6 mRNA correlated with the disease duration (p = 0.038, Pearson r = 0.493 and p = 0.038, Pearson r = 0.495, respectively). Splicing regulator ESRP1 expression positively correlated with CD44v6 expression in healthy controls (p = 0.02, Pearson r = 0.532) but not in SLE patients. The variant A allele of rs9666607 of CD44 was associated with higher level of global CD44 mRNA (p = 0.04) but not with the variant isoforms. CONCLUSIONS: In SLE patients, the increase in CD44v6 protein correlates with a higher transcript level of this isoform, confirming an impairment of CD44 splicing in the disease, whose regulatory mechanisms require further investigation.

The Heart Matters: Contribution of Genetic Factors in Recurrent Pericarditis.

BACKGROUND: Recurrent pericarditis is a state of repetitive inflammation of the pericardium with intervals of remission. The etiology of recurrent pericarditis is still largely unknown, yet most causes are presumed to be immune mediated. Genetic factors, including human leukocyte antigen (HLA) haplotypes, can be involved in dysregulation of the immune system and as a predisposition to several autoimmune conditions, including recurrent pericarditis. Several diseases are frequently associated with such manifestations. They include systemic lupus erythematosus, familial Mediterranean fever, and tumor necrosis factor receptor-associated periodic syndrome. However, idiopathic recurrent pericarditis remains the most frequently observed clinical condition and the conundrum of this disease still needs to be solved.

A multivariate genetic analysis confirms rs5010528 in the human leucocyte antigen-C locus as a significant contributor to Stevens-Johnson syndrome/toxic epidermal necrolysis susceptibility in a Mozambique HIV population treated with nevirapine.

Objectives: Nevirapine is used in developing countries for the treatment of HIV infection, but its use is associated with rare serious adverse reactions such as Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). Recently, an association between rs5010528 in the human leucocyte antigen (HLA)-C locus and SJS/TEN susceptibility has been described in sub-Saharan populations. Our aim was to verify this association in a population of nevirapine-treated patients from Mozambique. Methods: The rs5010528 SNP was analysed by direct sequencing in 27 patients who had developed SJS/TEN and 75 patients who did not develop adverse reactions after nevirapine treatment. A case-control association study was conducted. A multivariate analysis was performed in order to evaluate the role of HLA-C also in relation to other susceptibility genetic factors (CYP2B6, TRAF3IP2, HCP5, PSORS1C1 and GSTM1 genes). Results: rs5010528 was significantly associated with a higher risk of developing SJS/TEN; the variant allele was more frequent in cases than in controls, conferring a high risk of developing this adverse reaction in carriers (OR = 5.72 and P = 0.0002 at genotype level, OR = 3.51 and P = 0.0002 at allelic level). The multivariate analysis showed that the HLA-C SNP, CYP2B6 (rs28399499), TRAF3IP2 (rs76228616) and GSTM1 (null genotype) can explain 25% of the susceptibility to this reaction, with the HLA-C SNP as the most significant contributor (P = 0.02 and OR = 5.64). Conclusions: Our study confirmed the association of the rs5010528 SNP in the HLA-C region with susceptibility to developing SJS/TEN in a population from Mozambique, suggesting that it could be a good genomic biomarker for SJS/TEN susceptibility in different sub-Saharan populations.

Impact of glutathione transferases genes polymorphisms in nevirapine adverse reactions: a possible role for GSTM1 in SJS/TEN susceptibility.

PURPOSE: Nevirapine (NVP) is used in developing countries as first-line treatment of HIV infection. Unfortunately, its use is associated with common serious adverse drug reactions, such as liver toxicity and the most severe and rare Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). GSTT1 and GSTM1 genes code for enzymes involved in the metabolism of a wide range of drugs. We hypothesized that this gene variability could be implicated in NVP adverse reactions. METHODS: We analyzed the GSTM1 and GSTT1 null genotypes by multiplex PCR in a population of 181 patients from Mozambique, treated with NVP. A case/control association study was performed. We also counted the number of risk alleles in SJS/TEN patients and in controls, including the GSTM1 null genotype and four previously identified risk alleles in CYP2B6, HCP5, and TRAF3IP2 genes. RESULTS: Among patients, 27 had developed SJS/TEN and 76 had developed hepatotoxicity during the treatment. The GSTM1 null genotype was more frequent in the cases with SJS/TEN than in the controls (OR = 2.94, P = 0.027). This association is also observed when other risk factors are taken into account, by a multivariate analysis (P = 0.024 and OR = 3.58). The risk allele counting analysis revealed a significantly higher risk for SJS/TEN in patients carrying three or four risk alleles. Moreover, all subjects with five or six risk alleles developed SJS/TEN, while subjects without any risk alleles were present only in the control group. CONCLUSIONS: We observed an association between GSTM1 and SJS/TEN susceptibility. Moreover, GSTM1 contributes to the definition of a genetic risk profile for SJS/TEN susceptibility.

Cannabinoid Poisoning by Hemp Seed Oil in a Child.

We report a case of mild cannabinoid poisoning in a preschool child, after 3-week ingestion of hemp seed oil prescribed by his pediatrician to strengthen his immune system. The patient presented neurological symptoms that disappeared after intravenous hydration. A possible mild withdrawal syndrome was reported after discharge. The main metabolite of Δ-tetrahydrocannabinol was detected in urine, and very low concentration of Δ-tetrahydrocannabinol was detected in the ingested product. This is, as far as we know, the first report of cannabinoid poisoning after medical prescription of hemp seed oil in a preschool child.

A pharmacogenetics study in Mozambican patients treated with nevirapine: full resequencing of TRAF3IP2 gene shows a novel association with SJS/TEN susceptibility.

Steven-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are severe adverse drug reactions, characterized by extensive epidermal detachment and erosions of mucous membrane. SJS/TEN is one of the most serious adverse reactions to Nevirapine (NVP) treatment, commonly used in developing countries as first-line treatment of human immunodeficiency virus infection. In the last years TRAF3IP2 gene variants had been described as associated with susceptibility to several diseases such as psoriasis and psoriatic arthritis. We hypothesized that this gene, involved in immune response and in NF-κB activation, could also be implicated in the SJS/TEN susceptibility. We performed a full resequencing of TRAF3IP2 gene in a population of patients treated with NVP. Twenty-seven patients with NVP-induced SJS/TEN and 78 controls, all from Mozambique, were enrolled. We identified eight exonic and three intronic already described variants. The case/control association analysis highlighted an association between the rs76228616 SNP in exon 2 and the SJS/TEN susceptibility. In particular, the variant allele (C) resulted significantly associated with a higher risk to develop SJS/TEN (p = 0.012 and OR = 3.65 (95% CI 1.33-10.01)). A multivariate analysis by logistic regression confirmed its significant contribution (p = 0.027, OR = 4.39 (95% CI 1.19-16.23)). In conclusion, our study suggests that a variant in TRAF3IP2 gene could be involved in susceptibility to SJS/TEN.

HCP5 genetic variant (RS3099844) contributes to Nevirapine-induced Stevens Johnsons Syndrome/Toxic Epidermal Necrolysis susceptibility in a population from Mozambique.

PURPOSE: Nevirapine (NVP) is an anti-retroviral drug used for the treatment of HIV infection, that may cause several severe adverse events, including Stevens Johnsons Syndrome/Toxic Epidermal Necrolysis (SJS/TEN). A recent whole genome association study highlighted a strong association with allopurinol-induced SJS/TEN within the HCP5 and PSORS1C1 genes in the Japanese population. Our aim was to verify the contribution of these two genes in the susceptibility to NVP-induced SJS/TEN in a population from Mozambique. METHODS: Genotyping of PSORS1C1 rs2233945 and HCP5 rs3099844 SNPs was performed in a sample of 27 patients with SJS/TEN and 76 controls. A case-control and a haplotype analysis were performed. RESULTS: The HCP5 rs3099844 variant allele was significantly associated with the SJS/TEN susceptibility (OR = 2.03 and P = 0.039). The TA haplotype, carrying both the variant alleles of the two genes, showed a higher risk for developing SJS/TEN (OR = 3.44and P = 0.003). The regression analysis confirmed the contribution of HCP5 rs3099844 SNP (OR = 2.05, P = 0.047). By a log-linear model, we also investigated for interaction between HCP5 rs309844 and PSORS1C1 rs2233945 SNPs with respect to SJS/TEN risk, and we observed a strong interaction between the two SNPs (P = 0.005). CONCLUSIONS: We confirmed the association of HCP5 with the SJS/TEN susceptibility in a population from Mozambique treated with NVP.

Low expression levels of miRNA-155 and miRNA-499a are associated with obesity in Type 2 diabetes.

Background & aims: This study investigated a possible correlation between three circulating miRNAs, previously observed to be associated to diabetic polyneuropathy, and the obesity condition. Methods & results: The expression levels of miR-128a, miR-155 and miR499a were evaluated in 49 participants with Type 2 diabetes, divided into different groups based on the presence or absence of obesity and central obesity. The analyses revealed a significant decrease of miR-155 and miR-499a expression levels in obese subjects. In particular, the reduction appears to be even more significant in Type 2 diabetes subjects with central obesity. Conclusion: The results suggest that these miRNAs could be involved in obesity-driven pathogenetic mechanisms.

Study of lncRNAs expression profile in the response to biological drugs in Psoriatic Arthritis: MEG3 could be a potential genomic biomarker of therapy efficacy.

We aimed to identify an expression profile of lncRNAs potentially related to treatment response in Psoriatic arthritis (PsA) patients, to be used as potential genomic biomarkers predictors of drug treatment effectiveness. In addition, we evaluated a possible association between lncRNAs genetic variants and the response to therapy using the clinical parameter of Disease Activity Index. For the expression study, we collected 48 treated PsA patients, monitoring the treatment response for 12 months. We initially used PCR Array and, then, we validated the results with qRT-PCR. We also retrospectively genotyped 163 treated PsA patients. Firstly, we observed a significant difference in the expression level between Responder and non-Responder patients, of 4 lncRNAs in the group of PsA patients treated with TNFi and of 3 lncRNAs in the group of patients treated with IL17i. Then, we confirmed a significant decrease of MEG3 expression in non-Responder patients compared to Responders, also considering separately the single groups of patients treated with TNFi and IL17i. In addition, our results seem to highlight a potential dose-dependent effect of rs941576 (MEG3) variant allele on Disease Activity Index. Our study suggests a possible role of the lncRNA MEG3 in the treatment response to biological drugs.

The dysregulation of mitochondrial homeostasis-related genes could be involved in the decrease of mtDNA copy number in systemic lupus erythematosus patients.

Systemic lupus erythematosus (SLE) is a chronic multifactorial autoimmune disease. It is now widely demonstrated that oxidative stress (OS) plays an important role in the modulation of the pathogenesis of this disease. Mitochondrial DNA (mtDNA) is highly vulnerable to OS and it is known a decrease of mtDNA copy number in SLE patients. However, to date, it has not been investigated if this decrease is associated with a dysregulation of mitochondrial homeostasis genes. Our aim is to evaluate the amount of mtDNA copy number and the expression of the genes more involved in the mitochondrial homeostasis pathways, in peripheral blood mononuclear cells (PBMCs) of SLE patients and healthy controls. We analysed the amount of mtDNA in PBMCs of 72 SLE patients and 61 healthy controls by qPCR. Then, we investigated the expression variability of TFAM and SIRT1 (biogenesis), MFN1 and MFF (fusion/fission) and PRKN2 (mitophagy) genes in a subgroup of SLE patients and healthy controls. Interestingly, we have observed a highly significant decrease in mtDNA copies in SLE patients compared to healthy controls (P < 0.0001). In addition, we have shown that the expression levels of SIRT1, MFN1 and PRKN2 genes were significantly decreased in SLE patients with respect to healthy controls (P = 0.00001 for SIRT1, P = 0.0150 for MFN1 and P = 0.0009 for PRKN2). Lastly, we have reported a positive correlation between PRKN2 expression level and mtDNA copy number (P = 0.019, r = 0.475). In conclusion, our data confirm the impairment of mtDNA copy number in the disease and show for the first time a dysregulation of the mitochondrial homeostasis genes. These results could provide additional support to the important role of mitochondria in SLE development.

Large-scale DNA sequencing identifies rare variants associated with Systemic Lupus Erythematosus susceptibility in known risk genes.

The identification of rare genetic variants associated to Systemic Lupus Erythematosus (SLE) could also help to understand the pathogenic mechanisms at the basis of the disease. In this study we have analyzed a cohort of 200 Italian SLE patients in order to explore the rare protein-coding variants in five genes (TNFAIP3, STAT4, IL10, TRAF3IP2, and HCP5) already investigated for commons variants found associated in our previous studies. Genomic DNA of 200 SLE patients was sequenced by whole exome sequencing. The identified variants were filtered by frequency and evaluated by in silico predictions. Allelic association analysis was performed with standard Fisher's exact test. Introducing a cutoff at MAF < 0.01, a total of 19 rare variants were identified. Seven of these variants were ultra-rare (MAF < 0.001) and six were absent in the GnomAD database. For TNFAIP3 gene, the variant c.A1939C was observed in 4 SLE patients and it is located in a region enriched in phosphorylation sites and affects the predict affinity of specific kinases. In TRAF3IP2 gene, we observed 5 different rare variants, including the novel variant c.G410A, located in the region that mediates interaction with TRAF6, and therefore a possible risk factor for SLE development. In STAT4 gene, we identified 6 different rare variants. Among these, three missense variants decrease the stability of this protein. Moreover, 3 novel rare variants were detected in 3 SLE patients. In particular, c.A767T variant was predicted as damaging by six prediction tools. Concluding, we have observed that even in genes whose common variability is associated with SLE susceptibility, it is possible to identify rare variants that could have a strong effect in the disease development and could therefore allow a better understanding of the functional domain involved.

The rs11568820 Variant in the Promoter Region of Vitamin D Receptor Gene Is Associated with Clinical Remission in Rheumatoid Arthritis Patients Receiving Tumor Necrosis Factor Inhibitors.

The vitamin D receptor (VDR), binding to the active form of the vitamin, promotes the transcription of numerous genes involved in the proliferation of immune cells, cytokine production and lymphocyte activation. It is known that vitamin D deficiency can influence the risk of developing rheumatoid arthritis (RA) or modulate its disease activity. The aim of this study was to investigate a possible association between the rs11568820 (C > T) polymorphism in the promoter region of VDR gene and the response to therapy with anti-TNF drugs in patients with RA. A total of 178 consecutive Italian patients with RA treated with anti-TNF, naïve for biological therapy, were recruited. Disease activity data were evaluated using specific indices such as DAS28, CDAI and SDAI, measured at the start of therapy and subsequently at 22, 52, 104 and 240 weeks. A statistically significant association emerged between the rs11568820 variant allele of VDR gene and failure to remission assessed by CDAI and SDAI at 52 weeks, and by DAS28, CDAI and SDAI at 104 weeks of follow-up. Furthermore, the variant allele of this polymorphism was observed more frequently in patients who did not undergo sustained remission calculated by CDAI and SDAI. The variant T allele of rs11568820 in VDR gene is associated with a reduced remission rate with anti-TNFα drugs. These data suggest the role of VDR genetic variability in the response to therapy and in the achievement of remission.

TRAF3IP2 gene and systemic lupus erythematosus: association with disease susceptibility and pericarditis development.

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease. Although genetic factors confer susceptibility to the disease, only 15 % of the genetic contribution has been identified. TRAF3IP2 gene, associated with susceptibility to psoriatic arthritis and psoriasis, encodes for Act1, a negative regulator of adaptive immunity and a positive signaling adaptor in IL-17-mediated immune responses. The aim of this study was to assess the role of TRAF3IP2 gene variability in SLE susceptibility and disease phenotype in an Italian population. Two hundred thirty-nine consecutive SLE patients were enrolled. Study protocol included complete physical examination; the clinical and laboratory data were collected. Two hundred seventy-eight age- and ethnicity-matched healthy subjects served as controls. TRAF3IP2 polymorphisms (rs33980500, rs13190932, and rs13193677) were analyzed in both cases and controls. Genotype analysis was performed by allelic discrimination assays. A case-control association study and a genotype-phenotype correlation were performed. The rs33980500 and rs13193677 resulted significantly associated with SLE susceptibility (P = 0.021, odds ratio (OR) = 1.71, and P = 0.046, OR = 1.73, respectively). All three TRAF3IP2 single nucleotide polymorphisms resulted associated with the development of pericarditis; in particular, rs33980500 showed the strongest association (P = 0.002, OR 2.59). This association was further highlighted by binary logistic regression analysis. In conclusion, our data show for the first time the contribution of TRAF3IP2 genetic variability in SLE susceptibility, providing further suggestions that common variation in genes that function in the adaptive and innate arms of the immune system are important in establishing SLE risk. Our study also shows that this gene may affect disease phenotype and, particularly, the occurrence of pericarditis.

Association between CYP2B6 polymorphisms and Nevirapine-induced SJS/TEN: a pharmacogenetics study.

PURPOSE: Nevirapine (NVP) is a non-nucleoside reverse transcriptase inhibitor, widely prescribed for type 1 human immunodeficiency virus infection. A small proportion of individuals treated with NVP experience severe cutaneous adverse events, including Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN). Our aim was to verify whether genetic variability in NVP-metabolizing cytochromes or in transporter genes could be involved in susceptibility to SJS/TEN. METHODS: Twenty-seven patients with NVP-induced SJS/TEN and 78 controls, all from Mozambique, were genotyped for the ABCB1 and ABCC10 transporter genes and for CYP2B6, CYP3A4 and CYP3A5 cytochrome gene variants. A case-control and a genotype-phenotype analysis were performed. RESULTS: CYP2B6 G516T and T983C single nucleotide polymorphisms (SNPs) were found to be associated with SJS/TEN susceptibility. The 983C allele in particular was found to be highly associated with a higher risk to develop SJS/TEN [odds ratio (OR) 4.2, P = 0.0047]. The GT haplotype (wildtype for both SNPs) showed a protective effect, with an OR = 0.33 (P = 0.0016). CONCLUSIONS: This is the first study showing that genetic variability in a metabolizing enzyme can also contribute to NVP-induced SJS/TEN susceptibility.

PCSK3 Overexpression in Sjögren's Syndrome Patients May Be Regulated by rs4932178 SNP in Its Promoter Region and Correlates with IFN-γ Gene Expression.

BACKGROUND: The PCSK3 gene encodes for the protease enzyme Furin, which promotes proteolytic maturation of important regulators of the immune response, and also enhances the secretion of interferon-γ (IFN). Several studies have suggested its possible involvement in the pathogenesis of chronic inflammatory diseases. METHODS: We investigated the PCSK3 gene expression level in peripheral blood mononuclear cells isolated from Sjögren's Syndrome (SS) patients and healthy controls and we evaluated a possible correlation with IFN-γ gene expression. Moreover, we also explored the variability of two PCSK3 genetic polymorphisms (rs4932178 and rs4702) to evaluate a possible association between these polymorphisms and the expression levels of this gene. RESULTS: We observed, by RT-qPCR, that the PCSK3 expression level was significantly higher in SS patients compared to the controls (p = 0.028), and we confirmed a positive correlation between PCSK3 and IFN-γ expression levels (p < 0.001). Moreover, we reported that the variant homozygous genotype of rs4932178 SNP is associated with a higher expression of the PCSK3 gene (p = 0.038) and with the SS susceptibility (p = 0.016). CONCLUSIONS: Our data suggest that Furin could play a role in SS development, also promoting IFN-γ secretion.

Role of the Vitamin D Receptor (VDR) in the Pathogenesis of Osteoporosis: A Genetic, Epigenetic and Molecular Pilot Study.

The vitamin D receptor (VDR) regulates bone development and calcium homeostasis, suggesting a central role in musculoskeletal diseases such as osteoporosis (OP). Several studies have examined the contribution of VDR polymorphisms and epigenetic signatures in bone metabolism and OP risk, with sometimes inconclusive results. Our study aimed to explore the association between genetic variability, expression and the methylation pattern of VDR with the risk of OP in a cohort of Caucasian patients. Genomic DNA from 139 OP, 54 osteopenic (Ope) and 73 healthy (CTR) subjects were used for genotyping the rs731236 (TaqI), rs2228570 (FokI) and rs11568820 (Cdx2) polymorphisms of the VDR gene by an allelic discrimination assay. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis of VDR expression levels and pyrosequencing analysis of a VDR promoter CpG island were carried out in a subcohort (25 OP and 25 CTR) of subjects. Data obtained showed a significantly higher OP risk for rs11568820 G/A and A/A genotypes (p = 0.05). qRT-PCR revealed lower VDR gene expression levels in the OP group compared to CTR subjects (p = 0.0009), also associated with both the rs11568820 A/A genotype (p = 0.03) and femoral fragility fractures (p = 0.05). No association was found between the methylation pattern of the region analyzed of the VDR promoter and its expression levels. Our results identify a significative association between Cdx2 rs11568820 polymorphism and OP risk. In addition, the VDR transcriptomic profile suggests a putative interconnection with OP progression, providing a useful tool to stratify OP phenotype and fragility fracture risk.